People choose mates with similar life expectancy, researchers find

♦ Humans tend to unwittingly chose partners who have similar genetic risk factors to fatal illnesses and life expectancy, a study has found.

Experts at the University of Edinburgh claimed their findings explained why some long-term couples suffered from the same ailments in later years.

Researchers found people unconsciously selected mates who shared similar risks of illnesses, including high blood pressure or heart disease. They looked at information from the parents of couples and found that even in-laws shared genetic risk factors for diseases and shared a similar longevity.

The similarities were greater than would be expected by chance, suggesting people inadvertently chose a mate who shared the same disease risks. Given many ailments are not visible when people choose their partners, this was most likely to be a result of choosing a mate with shared lifestyle factors that are genetically linked to disease.

Joint risk behaviours, such as smoking, were most likely to lead to shared diseases in later life and, ultimately, a similar life expectancy.

Data from the UK Biobank, a major study of genes and lifestyle factors linked to health that involves more than half a million people, was examined for the research.

Prof Albert Tenesa said: “Understanding what traits these are will require new and long-term studies that follow hundreds of thousands of couples from the moment they meet.”